<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <script>
    //布尔类型  true   false
    let isVip = false;
    // console.log(isVip);

    // 数字类型  js中没有整形和浮点区分
    let age = 36;//10 进制
    let b = 0b11111111;//2 进制
    let o = 0o123;
    let x = 0xff;
    let t = 2;
    // console.log(typeof t);

    //字符串
    let s = '测试';
    let s2 = "看看人间的苦难，听听人民的呐喊";
    let s3 = `阶砖不会拒绝磨蚀，窗花不可幽禁落霞, ${s2}`;//字符串拼接

    // console.log(s3, typeof s3);

    // null
    // let n = null;
    // console.log(n);

    // undefined 未定义
    // let u = undefined;
    // let u2;

    // symbol 作用: 为对象添加独一无二的属性
    // let sy = Symbol();
    // console.log(sy, typeof sy);

    // 对象
    let santi = {
      //属性
      title: '三体',
      author: '刘慈欣',
      price: 19.9,
      //方法
      imagine: function(){
        console.log('提高想象力');
      }
    };
    console.log(santi, typeof santi);


    // usonb  undefined  string symbol  object number null boolean
  </script>
</body>
</html>